Questions tagged [cpu]
CPU is the abbreviation for central processing unit. Sometimes referred to simply as the central processor, but more commonly called processor
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What are the CPU architectures for the most common general purpose devices (i.e., Android, Windows/Linux PC, RaspberryPi etc.)? [closed]
Wikipedia lists over 45 different Instruction Set Architectures.
I would bet that most of those are listed for legacy purposes, but I barely have any knowledge on the subject (I'm not even sure if ...
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Is the maximum number of outstanding load instructions limited by the CPU architecture or the program?
I'm reviewing some lecture slides and had a question on the following slide :
Assumptions (8 clocks to transfer data) Up to 3 outstanding load requests.
The slide is illustrating that the number of ...
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Complicated task scheduling architecture
So I want to make an application in which a user will hit an endpoint to save a job model to storage that includes some metadata to perform a long computation against which will be offloaded to a ...
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I want my Docker container to use more of the host's CPU resources
I have a DigitalOcean droplet on which I have deployed a Docker container (Docker version: 20.10.14), but my app is sometimes slow, therefore I would like to allocate more resources to it.
The droplet ...
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Memory on multiple cores versus 1 core
I am running a program that, among other things, does some matrix multiplications, singular value decompositions and accessing matrix subsets on a very large data set (these are the lines of code that ...
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Memory Alignment
I want to make sure I understand the concept referred to by alignment:
Is it just a way of making sure that you never have a non-integer number of words? The wikipedia page says in order for an access ...
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Benchmarking C# code - results
I watch this YouTuber's mostly excellent videos on .NET features (let's call him Nick). He more often than not uses Benchmark.net to demonstrate the differences in performance of different approaches ...
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Can we reliably use unaligned scalars on contemporary hardware?
Processors have come a long way in their handling of unaligned data - from crashing at the very notion of it, through suffering severe penalties, all the way to having almost no impact.
I suppose it ...
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Why do modern operating systems *ever* have perceptible input (keyboard/mouse) lag?
Sometimes computers stutter a bit when they're working hard, to the point where the mouse location freezes for a fraction of a second, or stutters intermittently for a few seconds. This sometimes ...
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What is the benefit of equipping a computer or smartphone with multiple CPU cores that differ in clock speed? [closed]
I've bought a samsung galaxy s21 ultra about a year ago. Today i was looking at the specs again and i noticed that the Samsung Exynos 2100 processor consists out of 1 single CPU core of 2.9 GHz, three ...
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What happens when one thread is waiting to be executed while another is waiting for input?
Suppose I have two threads, A and B. A is waiting for input, while B is waiting to be executed. All other CPU cores are busy with CPU-bound tasks.
What will happen to A?
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Archival-quality future-proof pseudo-CPU architecture
Suppose we maintain a massive electronic library of texts/photos/videos etc., and want to ensure that these files are readable indefinitely long in the future. [Update] one of the major problems with ...
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Branch Prediction: How does a correlative branch predictor select from the global history?
I am trying to understand how branch prediction works, specifically with regards to correlative branch prediction. I understand that in an (m, n) branch predictor, there are m branch predictors, with ...
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Efficiency of different Processors and GPUs
My question is, knowing everything there is to know about several systems(CPU and GPU stats, OS), is it possible to approximate when each system will finish a specific processing operation?
And if it ...
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ALU and register relations
Does the ALU have its own memory or registers where it stores input operands etc. or does it only use CPU registers (that aren't only specifically used for ALU tasks)?
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How do binary numbers interact with the CPU and cause some action to take place? [duplicate]
EDIT: Perhaps what I am misunderstanding is that when it is said that the code we type gets turned into machine code of 0s and 1s. If these 0s and 1s are the abstracted representation of their ...
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How to anticipate a software future where ARM (potentially) replaces x86 in server and PCs? [closed]
With the introduction of Apple M1 processor, ARM has stood up to be a capable competitor and an alternative to x86 processors. We can foresee a future where ARM captures considerable market share of ...
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How to calculate the computing power gap of different CPUs
I want to compare the performance gap between the two machines, the main consideration here is memory and CPU. For example, the theoretical calculation peak of the CPU. Theoretical CPU peak = main ...
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Does it ever make sense to use more concurrent processes than processor cores?
I've got some process in Go. Here's an example counting lines in text, though the question is meant to be far more general than this particular example:
func lineCount(s string) int {
count := 0
...
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How does an OS limit a program capabilities, if it's working directly with the cpu?
When a program loads into memory and starts running, the cpu loads each instruction from the code and executes the instruction based on the opcode and the arguments, so, the program interracts so to ...
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Why is multithreading not used everywhere?
Not almost, but all modern CPUs have multiple cores, yet multithreading isn't really that common. Why to have these cores then? To execute several sequential programs at the same time? Well, when ...
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Where on the 64bit memory of a PC would one byte end up?
I have a simple question I think.
A typical pc with ram has a 64bit databus between the cpu and ram. Let's say the ram starts at address 0, and I write i byte to address 0. Now my question is, would ...
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Is it possible to update exactly 1 byte in RAM?
For example I have a static C++ array {'d', 'o', 'c', 's'}. And I have x86 architecture, with 32-bits length words.
I want to replace letter c with g. As far as I understand, when we make a read ...
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How specific is hardware optimization when building from source/how do I know?
How specific is hardware optimization when building from source and what should I look for in the documentation to decide if building for my hardware might be worth it?
From threads like this one I ...
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Why can't we vertically scale a system infinitely?
When talking about scaling a system, it's often said that vertical scaling has limitations. So after a point, we need to scale the system horizontally.
What are the limitations of:
Main memory - ...
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How to speed up my software development workflow? I'm using Visual Studio 2019 to build, compile, run tests for dotnet, C#, Docker containers, etc
I am primarily working with C#, dotnet and Visual Studio 2019 with extensions like Resharper enabled. Visual Studio with Resharper is a memory hog.
I currently have the following PC at home where I ...
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How are electrons moved in processors/CPU? [duplicate]
During our class, he posed the question 'How are electrons moved by code' for our own reflection, the question seems to be vague but I assumed how are electrons moved in a processor/CPU since we were ...
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Does accessing RAM from 2 threads double access time (synchronous access)?
As in topic.
If i want to access RAM from 2 different threads, completly different cells in memory, do they queue and are sent asynchronously or queue?
Lets say accessing memory from one thread (...
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How is it possible for a process to use less than 100% CPU?
I don't know too terrible much about the CPU, but I know it processes assembly instructions and that Windows can say that it is at anywhere from 1-100% usage. How is it possible for a program to use ...
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What are the restrictions for the CPU when it is in user mode?
I know that when the CPU is in user mode, it can't access all memory, it also can't execute some CPU instructions (called "privileged instructions" I believe).
But are these two restrictions the only ...
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